Sludge drying system and method based on clean energy

Abstract

The invention discloses a sludge drying system based on clean energy. The sludge drying system comprises a sludge feeding treatment unit, an energy heat supply unit, a drying reaction unit, a sludge-gas separation unit and a tail gas treatment unit, the energy heat supply unit is used for supplying heat energy to the drying reaction unit, the sludge-gas separation unit is used for separating dried sludge and tail gas, and the tail gas is treated by the tail gas treatment unit and then is discharged after reaching the standard; the sludge feeding treatment unit is used for carrying out feeding pretreatment on wet sludge, including regulating the particle size of the sludge and adjusting the water content of the sludge. Compared with the prior art, the sludge drying system and the sludge drying method based on the clean energy have the advantages that the sludge drying system and the sludge drying method based on the clean energy are based on the clean energy, feeding is controllable, and tail gas reaches the standard and is discharged.

Description

Technical Field

[0001] This invention relates to the field of sludge resource utilization technology, specifically to a sludge drying system and drying method based on clean energy. Background Technology

[0002] With the acceleration of urbanization, the amount of sludge produced by sewage treatment plants has increased dramatically. Sludge has a high water content, is easily putrefied, and contains pathogens and heavy metals. Improper disposal can cause serious secondary pollution to the environment.

[0003] Currently, sludge drying is a key pretreatment step for achieving sludge reduction, stabilization, and resource utilization.

[0004] Existing sludge drying technologies mostly rely on natural gas, coal, or electricity as heat sources, resulting in high operating costs. Furthermore, the poor adaptability of feed materials means that direct feeding into the dryer can easily cause sticking and clumping, leading to a decrease in heat transfer efficiency and difficulty in controlling the final moisture content. The exhaust gas generated during the drying process contains a large amount of dust, water vapor, volatile organic compounds (VOCs), and malodorous gases. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the above-mentioned technical defects and provide a sludge drying system and drying method based on clean energy, with controllable feed and compliant exhaust emissions.

[0006] To solve the above-mentioned technical problems, the technical solution provided by the present invention is: a sludge drying system based on clean energy, including a sludge feeding and processing unit, an energy heating unit, a drying reaction unit, a sludge-gas separation unit and an exhaust gas treatment unit;

[0007] The energy heating unit supplies heat to the drying reaction unit, and the sludge-gas separation unit separates the dried sludge and exhaust gas after drying. The exhaust gas is treated by the exhaust gas treatment unit and then discharged in compliance with standards.

[0008] The sludge feeding and processing unit performs pretreatment on the wet sludge, including standardizing the sludge particle size and adjusting the sludge moisture content.

[0009] Preferably, the sludge feeding and processing unit includes a crushing mechanism, a screening mechanism, and a moisture conditioning mechanism;

[0010] The crushing mechanism breaks large pieces of wet sludge into uniform small particles, and the screening mechanism removes particulate impurities from the sludge.

[0011] The humidity control mechanism mixes the crushed sludge with some of the dried remixed sludge to adjust the initial moisture content and viscosity of the sludge entering the drying reaction unit.

[0012] Preferably, the energy heating unit includes at least one of solar energy and biomass energy, and a heat exchange component is provided between the energy heating unit and the drying reaction unit;

[0013] It also includes a heat storage buffer unit, which is connected to the energy heating unit and the drying reaction unit respectively, to store excess heat energy and release heat energy when the energy supply is insufficient.

[0014] Preferably, the drying reaction unit is an indirect heating and drying device, which has a jacket layer inside and a high-temperature heat medium inside the jacket layer, which transfers heat to the sludge through the metal wall.

[0015] Preferably, the sludge-gas separation unit includes a separator and a dust collector, the inlet of the separator is connected to the outlet of the drying reaction unit, and the inlet of the dust collector is connected to the gas phase outlet of the separator.

[0016] Preferably, the exhaust gas treatment unit includes a heat exchanger, a scrubbing tower, and a biological deodorization component connected in sequence;

[0017] The heat exchanger recovers waste heat from the exhaust gas, the scrubbing tower removes particulate matter and soluble pollutants from the exhaust gas, and the biological deodorization component degrades organic odorous substances in the exhaust gas.

[0018] Preferably, the heat recovered by the heat exchanger is returned to the heat storage buffer unit via a circulating medium.

[0019] Preferably, it also includes a control unit;

[0020] The control unit is electrically connected to the sludge feeding and processing unit, the energy heating unit, and the drying reaction unit. Based on the temperature parameters in the drying reaction unit and the moisture content of the sludge at the outlet, it adjusts the feeding speed and the amount of heat energy supplied.

[0021] Another aspect of this invention discloses a sludge drying method based on a clean energy-based sludge drying system, comprising the following steps:

[0022] S1: Crush and screen wet sludge to regulate particle size and remove particulate impurities;

[0023] S2: Mix the crushed sludge with some dried and remixed sludge and adjust the moisture content and viscosity to the preset initial moisture content and viscosity, then transport it to the drying reaction unit.

[0024] S3: Utilizes solar or biomass energy to generate heat, which is then transferred to the drying reaction unit via heat exchange components;

[0025] S4: The pretreated sludge is sent into the drying reaction unit, where it is dehydrated and dried by indirect heat transfer through the metal wall via the high-temperature heat medium in the internal jacket layer.

[0026] S5: After drying, the sludge-gas mixture enters the sludge-gas separation unit, where solid dry sludge and gaseous tail gas are separated. The separated tail gas is then transported to the tail gas treatment unit.

[0027] S6: The exhaust gas passes through the exhaust gas treatment unit in sequence through a heat exchanger to recover waste heat, a scrubbing tower to remove particulate matter and soluble pollutants, and a biological deodorization component to degrade organic odorous substances, finally meeting emission standards.

[0028] S7: The heat storage buffer unit releases heat energy to the drying reaction unit when the energy supply is insufficient.

[0029] The advantages of this invention compared to existing technologies are: this invention makes full use of renewable energy sources such as solar energy and biomass energy, which significantly reduces fossil energy consumption and carbon emissions;

[0030] In this invention, the heat storage buffer unit effectively mitigates the fluctuations in clean energy, ensuring the continuity and stability of the drying process.

[0031] The exhaust gas treatment system of this invention integrates three-stage processes: waste heat recovery, washing and purification, and biological deodorization, which not only recovers energy but also completely eliminates dust and odor pollution. Attached Figure Description

[0032] Figure 1 This is a flowchart illustrating the sludge drying method. Detailed Implementation

[0033] The present invention will now be described in further detail with reference to the accompanying drawings.

[0034] Combined with appendix Figure 1 As shown, a sludge drying system based on clean energy mainly consists of a sludge feeding and processing unit, an energy heating unit, a drying reaction unit, a sludge-gas separation unit, an exhaust gas treatment unit, a heat storage buffer unit, and a central control unit.

[0035] In use, the sludge feeding and processing unit includes a crushing mechanism, a screening mechanism, and a moisture conditioning mechanism;

[0036] The crushing mechanism breaks large pieces of wet sludge into uniform small particles, and the screening mechanism removes particulate impurities from the sludge.

[0037] The humidity control mechanism mixes the crushed sludge with some of the dried remixed sludge to adjust the initial moisture content and viscosity of the sludge entering the drying reaction unit.

[0038] In one embodiment:

[0039] The energy heating unit includes at least one of solar energy and biomass energy, and a heat exchange component is provided between the energy heating unit and the drying reaction unit;

[0040] It also includes a heat storage buffer unit, which is connected to the energy heating unit and the drying reaction unit respectively. It stores excess heat energy and releases heat energy when the energy supply is insufficient. The drying reaction unit is an indirect heating and drying device with a jacket layer inside. The jacket layer contains a high-temperature heat medium, which transfers heat to the sludge through the metal wall.

[0041] In one embodiment:

[0042] The mud-gas separation unit includes a separator and a dust collector. The inlet of the separator is connected to the outlet of the drying reaction unit, and the inlet of the dust collector is connected to the gas phase outlet of the separator. The tail gas treatment unit includes a heat exchanger, a scrubbing tower and a biological deodorization component connected in sequence. The heat recovered by the heat exchanger is returned to the heat storage buffer unit through a circulating medium.

[0043] The heat exchanger recovers waste heat from the exhaust gas, the scrubbing tower removes particulate matter and soluble pollutants from the exhaust gas, and the biological deodorization component degrades organic odorous substances in the exhaust gas.

[0044] To facilitate intelligent control, a control unit is also included;

[0045] The control unit is electrically connected to the sludge feeding and processing unit, the energy heating unit, and the drying reaction unit. Based on the temperature parameters in the drying reaction unit and the moisture content of the sludge at the outlet, it adjusts the feeding speed and the amount of heat energy supplied.

[0046] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0047] Working principle: The sludge feeding and processing unit pre-treats the wet sludge, including a crushing mechanism that crushes large pieces of wet sludge into uniform small particles, followed by a screening mechanism that removes particulate impurities from the sludge, effectively regulating the sludge particle size and creating favorable conditions for subsequent drying. Then, the moisture conditioning mechanism mixes the crushed sludge with some of the dried return sludge, adjusting the initial moisture content and viscosity of the sludge entering the drying reaction unit, reducing material stickiness, preventing equipment from sticking to the walls and clumping, and improving heat transfer efficiency.

[0048] The pretreated sludge is transported to the drying reaction unit, which uses an indirect heating and drying equipment. The equipment has a jacket layer inside, and a high-temperature heat medium flows inside the jacket layer. The heat is transferred to the sludge through the metal wall, which realizes the dehydration and drying of the sludge. This method not only has high thermal efficiency, but also effectively reduces the amount of exhaust gas generated.

[0049] The heat energy source of this invention is provided by an energy heating unit, which utilizes at least one of solar energy and biomass energy to generate heat energy. To address the problem of unstable clean energy supply, a heat storage buffer unit is set up between the energy heating unit and the drying reaction unit. This unit can store excess heat energy and release it when solar energy is insufficient or biomass energy supply fluctuates, ensuring a continuous and stable heat energy supply and guaranteeing the continuity of the drying process. The heat energy is transferred to the jacket layer of the drying reaction unit through heat exchange components to drive the drying process.

[0050] After drying, the resulting mud-gas mixture enters the mud-gas separation unit, which includes a separator and a dust collector. The separator initially separates the dried solid sludge from the gaseous exhaust gas, and then the dust collector further removes fine dust from the exhaust gas, ensuring the purity of the dried sludge product.

[0051] The separated exhaust gas then enters the exhaust gas treatment unit for deep purification. The exhaust gas first recovers waste heat through a heat exchanger, and the recovered heat is returned to the heat storage buffer unit through a circulating medium, realizing the cascade utilization of energy and further reducing system energy consumption.

[0052] After cooling, the exhaust gas enters the scrubbing tower to remove particulate matter and soluble pollutants; finally, it passes through the biological deodorization component to degrade organic odorous substances in the exhaust gas, ensuring that the final emissions meet the standards and effectively eliminating secondary pollution.

[0053] In practical applications, the operation of this invention is uniformly coordinated by a control unit. The control unit is electrically connected to the sludge feeding and processing unit, the energy heating unit, and the drying reaction unit, and monitors the temperature parameters within the drying reaction unit and the moisture content of the outlet sludge in real time. Based on this real-time data, the control unit automatically adjusts the feeding rate and heat supply, achieving intelligent closed-loop control of the system and ensuring the stability of the dried product quality and the high efficiency of operation.

[0054] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0055] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A sludge drying system based on clean energy, characterized in that: It includes a sludge feeding and treatment unit, an energy heating unit, a drying reaction unit, a sludge-gas separation unit, and an exhaust gas treatment unit; The energy heating unit supplies heat to the drying reaction unit, and the sludge-gas separation unit separates the dried sludge and exhaust gas after drying. The exhaust gas is treated by the exhaust gas treatment unit and then discharged in compliance with standards. The sludge feeding and processing unit performs pretreatment on the wet sludge, including standardizing the sludge particle size and adjusting the sludge moisture content.

2. The sludge drying system based on clean energy according to claim 1, characterized in that: The sludge feeding and processing unit includes a crushing mechanism, a screening mechanism, and a moisture conditioning mechanism; The crushing mechanism breaks large pieces of wet sludge into uniform small particles, and the screening mechanism removes particulate impurities from the sludge. The humidity control mechanism mixes the crushed sludge with some of the dried remixed sludge to adjust the initial moisture content and viscosity of the sludge entering the drying reaction unit.

3. The sludge drying system based on clean energy according to claim 1, characterized in that: The energy heating unit includes at least one of solar energy and biomass energy, and a heat exchange component is provided between the energy heating unit and the drying reaction unit. It also includes a heat storage buffer unit, which is connected to the energy heating unit and the drying reaction unit respectively, to store excess heat energy and release heat energy when the energy supply is insufficient.

4. The sludge drying system based on clean energy according to claim 1, characterized in that: The drying reaction unit is an indirect heating and drying device with an internal jacket layer containing a high-temperature heat transfer medium that transfers heat to the sludge through the metal wall.

5. The sludge drying system based on clean energy according to claim 1, characterized in that: The mud-gas separation unit includes a separator and a dust collector. The inlet of the separator is connected to the outlet of the drying reaction unit, and the inlet of the dust collector is connected to the gas phase outlet of the separator.

6. The sludge drying system based on clean energy according to claim 1, characterized in that: The exhaust gas treatment unit includes a heat exchanger, a scrubbing tower, and a biological deodorization component connected in sequence. The heat exchanger recovers waste heat from the exhaust gas, the scrubbing tower removes particulate matter and soluble pollutants from the exhaust gas, and the biological deodorization component degrades organic odorous substances in the exhaust gas.

7. A sludge drying system based on clean energy according to claim 6, characterized in that: The heat recovered by the heat exchanger is returned to the heat storage buffer unit through the circulating medium.

8. The sludge drying system based on clean energy according to claim 1, characterized in that: It also includes a control unit; The control unit is electrically connected to the sludge feeding and processing unit, the energy heating unit, and the drying reaction unit. Based on the temperature parameters in the drying reaction unit and the moisture content of the sludge at the outlet, it adjusts the feeding speed and the amount of heat energy supplied.

9. A sludge drying method for a sludge drying system based on clean energy according to any one of claims 1 to 8, characterized in that: Includes the following steps: S1: Crush and screen wet sludge to regulate particle size and remove particulate impurities; S2: Mix the crushed sludge with some dried and remixed sludge and adjust the moisture content and viscosity to the preset initial moisture content and viscosity, then transport it to the drying reaction unit. S3: Utilizes solar or biomass energy to generate heat, which is then transferred to the drying reaction unit via heat exchange components; S4: The pretreated sludge is sent into the drying reaction unit, where it is dehydrated and dried by indirect heat transfer through the metal wall via the high-temperature heat medium in the internal jacket layer. S5: After drying, the sludge-gas mixture enters the sludge-gas separation unit, where solid dry sludge and gaseous tail gas are separated. The separated tail gas is then transported to the tail gas treatment unit. S6: The exhaust gas passes through the exhaust gas treatment unit in sequence through a heat exchanger to recover waste heat, a scrubbing tower to remove particulate matter and soluble pollutants, and a biological deodorization component to degrade organic odorous substances, finally meeting emission standards. S7: The heat storage buffer unit releases heat energy to the drying reaction unit when the energy supply is insufficient.

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